1. Technical Field
The present invention relates to endoscopy, and more particularly to a method for positioning an endoscope and an auxiliary positioning device used in the method.
2. Description of Related Art
Before inserting an endoscope into a patient's body cavity, medical professionals have to first position a point of incision at the surface of the body cavity. Only after the point of incision is well positioned, the endoscope can be sent into the patient's body cavity through the point of incision. In the conventional positioning technology, as one described in U.S. Pat. No. 5,697,939, two abreast image-projecting devices are used to project images on the targeted body cavity and the site where the two images coincide is the point of incision. However, such a positioning process is time-consuming and unfavorable to medical treatment. In addition, since the surface of the body cavity is not flat and even, the projected images tend to have distortion and cause errors in positioning. Another known positioning method is to use a scale to determine the relative position between the virtual center of the robot arm and the point of incision on the body cavity. However, in use of the scale, the scale is unavoidably contacted with the surface of the body cavity, so the risk of infection at the cut is relatively high. This approach also has the problems related to undulation and unevenness of the surface of the body cavity, so errors may happen if the scale is not placed perfectly.